The American Animal Hospital Website has information about most types of pets.
The Food and Drug Administration website has information about medications.​
Hill's Petfood community.  Contains helpful information on raising healthy pets and keeping them healthy throughout their life.  Not just food.​
The Internet contains much helpful information but also contains much that is misleading and often unproven and untrue.  Below are several links to sites that strive to only publish scientifically accurate information:
Veterinary Partner has health, behavior and general pet information.  It is one of the most helpful sites we have found.

Pet Health Answers/Links